Heater or superheater for steam, air, or gases



R. H. CABENA.

HEATER 0R SUPERHEATER FOR STEAM,AIR, 0R GASES.

APPLlCATION FILED mum. 1915.

1,332,943 Patented Mar. 9, 1920 Fay. 2. ,5

H H [I H II II A ma UNITED STATES PATENT OFFICE.

RICHARD HANSON CABE'NA, OF CROYDON, ENGLAND.

HEATER OR SUPERHEATER FOR STEAM, AIR, 0R GASES.

T 0 all whom it may concern:

Be it known that I, RICHARD HANSON CA- BENA, a subject of the King ofGreat Britain, residing at 120 Sydenham road, in the county borough ofCroydon and county of Surrey, England, have invented Improved Heaters orSuperheaters for Steam, Air, or Gases, of which the following is aspecification.

My invention relates to steam, air or gas heaters or superheaters and isintended more particularly for application to steam generators, andespecially for a superheater for use in connection with vertical steamboilers.

In steam 'superheaters it is common to employ what are known as fieldtubes, consisting of an inner open ended, or through, tube and anenveloping tube closed at the outer, or free, end,dependent from atwo-chamber header, or field tubes arranged horizontally.

According to the present invention, I employ inverted field tubesstanding up from a two-chamber header and arrange in combinationtherewith one or more deflectors or dampers which stand in or arearranged to be brought into a position obliquely to the path of the fluegases and direct the hot flue gases from the uptake or flue over aroundand among the said tubes. These deflectors may be adjustable as toposition and may also be pivoted, balanced and geared together, ifdesired. One or more further deflectors may be employed to direct thehot gases from the upper part of said tubes to the exterior of thedevice, and these upper deflectors may also be geared to the lowerdeflectors so as to move simultaneously therewith in order that bothupper and lower deflectors, when required, may be folded parallel withthe tubes and shut off the flue gases altogether from the superheater.

The field tubes may be fitted at intervals in their height with grids tokeep themin proper position. The space between the outer and inner tubesis very small so as to insurea high velocity of the air, gas or steampassing down between the outer and the inner tubes. The steam, air orgas enters the lower chamber of the header and is there distributed toand passes up through the inner tubes of the field couples, and returnsto'the upper or collecting chamber of the header, through the annularspace he Specification of Letters Patent.

Patented Mar. 9, 1920.

Application filed .Tune 3, 1915. Serial No. 32,838.

tween the inner and outer tubes. In its passage it becomes heated orsuperheated by contact with, and radiation from, thehot Walls of thetubes. From the collecting chamber it is drawn oil at any suitable pointfor transmission to the steam engine, or machine, or apparatus whereinit may be required to be used.

The objects of the improvements are, first, to regulate the amount ofheat or superheat according to requirements; second, topermit of easycleaning of the heating surfaces; third, to eflect a high degree of heatabstraction per unity of surface, and a high degree of superheat;fourth, in the case of vapors such as Wet steam, to effect a naturaldrainage, to reduce the carrying over of liquid particles, anddeposition of solid matters that may be contained therein.

As applied to a vertical boiler (see Figs. 1, 2, 3) the superheater isarranged beside the chimney or uptake and above the crown of the boilerin such a way as to provide a lateral chamber or chambers through whichthe flue gases are or can be directed when the superheater is requiredto operate.

The flue gases meet a deflector adapted to stand obliquely to the pathof the gases and to direct them on to the lower part of the nest oftubes of the heater or superheater. The gases then rise around thesetubes and pass away therefrom atthe top of the de vice. A seconddeflector may if desired be arrangcdabove the first to direct the escapeof the hot gases. These deflectors may be geared together so as to bebalanced and move simultaneously and to shut ofl the su-.

perheater when required.

In the accompanying drawings I have shown a superheater adapted to .workwith a vertical boiler.

Figure 1. is a sectional elevation of the superheater, on the line A -Bin Fig. 3.

Fig. 2. is an elevation viewed in the direction A to B in Fig. 8, and inpart section on CD in Fig. 1. with the plate 1. removed.

Fig. 3 is a plan of Fig. 1. with the chimney plate 2, and cleaning door3, removed.

Fig. 4. is a sectional elevation showing a method of forming and fixingthe inner and outer tubes of the field couples so as to form stays forthe flat surfaces oflarge headers.

In these drawings similar numerals refer to similar parts.

The superheater device is constructed with collecting spaces. the upper(5) and the middle (7) walls of the box-chamber receiving the open endsof the respective sets of tubes 4:, 6. The tubes l and 6 are (at top)preferably of square or similar section at their tops so as to take akey or spanner for the insertion or removal of the tubes. The internaltubes are with advantage reduced in cross sectional area for a shortdistance at their upper ends to cause a high velocity of steam at exit.A cleaning and inspection cover or door is shown at 3.

On the drawings, see Fi 1, pivoted flaps or deflector doors 8, 9, areprovided to regulate the path of the hot gases, the two flaps beingconnected together if desired for 8X' ample by means of intermeshingpinions 10, 11, upon their spindles, preferably in such a manner thatthey balance each other. By means of these'two deflectors thesuperheater can be shut off from the flue gases as occasion may requirefor cleaning the tubes or for repairs, while allowing ordinary use ofthe boiler. These deflectors also allow the control of the quantity ofthe gases passing to the tubes. The upper reflector also serves toprevent the formation of eddies in the upper part of the superheater andassists in directing the flue gases outwardly from the apparatus. Thepinions 10, 11, are shown controlled by a single operating lever 12,balanced and adapted to engage a notched rack 13 mounted on the exteriorof the shell of the superheater device; see Fig. 3.

The other sides oil the superheater chamber may be inclosed by means ofplates fitted together in a detachable manner so as readily to permitaccess for cleaning and inspection. Doors may be provided for inspectionor cleaning purposes.

The box-chamber which forms the header of the superheater and comprisesthe tube plates 5, 7, is preferably mounted on a rectangular flange 14,extending to one side from a base plate 15, which fits upon the upperend of the uptake or the motake-liner of the boiler. This box chambercomprises a lower inlet chamber 17 having an inlet 17 and an upperoutlet chamber 16 having an outlet 16.

The ath of the hot gases from the uptake of the boiler is deflect-ed bythe flap 9, which assists in directing the gases out through 20.

It will be evident that two or more superheater sections or nests oftubes may be provided around the boiler flue, either on the same or on.opposite sides, the headers and tubes being coupled in series or inparallel. One or more separate deflectors or pairs of deflectors may beprovided for the several sections. In other words, the superheater shownin Fig. 1 may be duplicated on the other side of the boiler uptake andflaps or deflectors be employed to direct and spread the hot flue gasestoward each set of tubes, the flaps being geared together and movablesimultaneously if desired.

The upper deflector 8 may be dispensed with if desired, or a singlepivoted deflector may be arranged to swing either up or down or to takeup a horizontal position, when the superheater is in use.

The superheater tubes may be cleaned by means of steam jets, aperforated tube being placed inside the casing for example. Scrapers maybe provided to clean the tubes, of ordinary construction.

Since the tubes at are supported only at their lower ends I may ifdesired fit a grid or grids (not shown) over or around the tubes 1, ator toward their upper portions, so as to keep the tubes parallel withone an other. Other grids may also be provided as baflle plates lowerdown the tubes 4. These intermediate grids would not extend around allthe tubes but would cause the hot flue gases to follow a zig-zag orsinuous path in their upward movement around and along the tubes 4:. Thegrids may be rigidly secured to the casingpf the apparatus.

The tubes 4, 6, are secured in place by screwing into tapped holes intheir respective tube-plates. Calking rings 21, Fig. l, may be providedaround the tubes 4, the latter preferably having a slight taper to thethreaded portion, and the countenbore in the tube-plate 5beingrough-machined to receive the calking, ring. These rings should beof metal having the same expansion approximately under heat, as themetals of the Ill) tube 4, and into the third wall 22 of the header.versely through the two tubes 4, 6, to allow passage of steam, and ascrew plug 26 closes the end of the internal tube. The whole arrangementresembles a boiler stay-tube and presents many advantages in practicewhen used on large headers with otherwise unsupported flat surfaces.

The tubes are preferably arranged in the vertical position described, soas to facilitate drainage. By the inverted arrangement of field tubesvertically or approximately so, drainage by gravitation is attained. Byproviding only a small annular space (for instance 3 2 or between thetubes a high velocity of steam is obtained whereby a higher rate ofabsorption of heat is gained and a higher degree of superheat' The highsteam velocity also clears away or prevents accumulation of deposit frommoist steam that would otherwise take place to the detriment of heatabstraction and causing blocking of the passages. The increase in rateof heat absorption enables shorter tubes to'be used and less extent oftube surface. The smaller outlet ends of the inner tubes dis charge thesteam at a high velocity near the closed ends of the outer tubes and inthis manner clear away or prevent any deposits which might otherwiseoccur.

In some cases the deflector may be a fixture of refractory material butI prefer to employ a deflector which is adjustable as to position. Whenthe deflectors are of metal they may have a saving-plate attached of theusual type and any suitable form easily renewable.

Sliding dampers or deflectors passing through a slot or opening in thewall of the casing adapted to direct the flue gases into the superheatermay be employed.

When applied to other types of boilers Holes 24, 25, are drilled trans-'than the vertical type the casing or shell, or portions, thereof, may beformed by the brickwork of the boiler setting, or by the easing of theboilers "or flues where these are of metal.

The invention may also be applied to the heating of gases or of air 6.g. for use with oil burners or supplying hot air to furnaces in whichcase the separator device would be dispensed with. The air would bepassed through the apparatus on its way from the air blower to theburner in a like manner to the passage of steam.

1 The part of the superheater comprising the tubes and header may bemade detachable from the deflector-provided portion if desired.

Having now particularly described and ascertained the nature of my saidinvention, and in what manner the same is to be performed, I declarethat what I claim is In a system of the class described a heatconducting flue, a superheater embodying a casing, a plurality ofvertical inverted field-type outer and inner tubes therein, uniformlyself-balancing externally geared deflector-doors arranged in pairs toopen or close communication between the flue and the casing and havingan oscillating movement, said doors being constructed and arranged as todirect the hot flue gases from the flue toward, on to, and among thesaid

